A testing method adapted for an electronic device operating an operating system at a particular temperature environment is provided. The method includes the steps of: determining whether an operating command is received; when the operating command is received, deriving a test, executing the test, and disabling a fan of the electronic device, wherein the test corresponds to one of a plurality of system states of an operating system, and includes a temperature threshold value corresponding to the system state and an entering action of the system state; and when the system state of the test corresponds to a work mode of the operating system, the test includes: continuously monitoring a temperature value of the central processing unit; and when the temperature value of the central processing unit reaches the temperature threshold value, enabling the fan and executing the entering action of the system state.